Data collection aboard the RV Oceanus: OC2006A

by | Jul 7, 2020 | Cascadia H.O.P.S, Education

Aboard RV Oceanus OC2006A, we will be using various sediment collection techniques, and data measurements for the materials collected. This introduction series of blogs will provide a base understanding of these systems and data that are useful for oceanography.

Our coring techniques include Piston Cores, Gravity Cores and Multi-Core. Our sample collection and shipboard measurements consist of pore water chemistry, multi-sensor track, and Plankton Net tows. Below are some images of each of our tools; in the coming days, we will update you on our travels and provide a more detailed description of how the instruments are used and what we can learn from them.

Piston and gravity core: Used to obtain 10-13 m cores; we hope to capture records of the last ice age (~20,000 years ago) at most sites. The records can help us better understand glacial retreats.
Multi-core: used to collect multiple short 0.25 m cores to study the sediment-water interface.
The centrifuge sits on a gimble plate to negate bobbing from the ship.
The squeezer will be used to retrieve pore water from the multi-core and gravity core systems for analysis. The squeezer along with the centrifuge will be used to collect and analyze pore-water chemistry. Seawater and water in the sediment are chemically different due to bacterial metabolism. Pore water chemistry will help us better understand the past carbon cycle and oceanography of the region.
Multi-Sensor Track: will be used to measure magnetic susceptibility, gamma ray attenuation, electrical resistivity, and p-wave velocity. This will help characterize the sediments before the cores are split.
Plankton Net Tows: used to collect present-day plankton samples to better understand changes in past climate.
Sediment core descriptions: A visual description of what we see in the split cores, also known as half rounds. Our cores will not be split until they are returned to the Marine and Geology Repository. This picture is from a previous cruise that used Kasten Cores that have square cores rather than the round cores we will be using.